Gents, I backed myself into a corner. I am pretty good with vehicles and have never came across this havoc I have created. Up front, I have a TBI which has made me make very easy mistakes. My 95 runner, 3.0, 3VZE ran great with 16 mpg. I got an EGR code occasionally which cleared up with some LUCAS. It started with a rough idle and I suspected injectors because it went away with some Lucas. I milked it as much as I could, but then the EGR code came with a MAF and IAT code. I replace the MAF which is should take care of the MAF and IAT. I replaced the injectors. My mistake was trying to compensate by adjusting my air/fuel adjustment screw to make the engine compensate. Even worse, I adjusted my timing to the bad air fuel mixture. I also found a slight air leak in my air intake. I have fought so hard to win this one, but I'm to the point of taking it to somebody. Last ditch effort. Give me some ideas. My biggie is getting the air/fuel screw back to standard.

 

Ever Toyota truck I have worked on, the EGR has put carbon in the Intake and clogged several rubber hoses. The EGR usually requires cleaning to get it operating again from my experience. If it was me, first I would clean the EGR, the Intake, all ports and hoses and then do a complete tune up and set my truck back to the factory specs according to the manual.

This is for a 22re but should give you an idea of what you need to do to get the EGR functioning>>>> https://www.yotatech.com/forums/f199...l#post51647988 >>>>

 

Terry, thanks for the reply and I should have included this information in my post: New plugs, wires, distributor cap/rotor, cleaned the EGR, but I have not checked the vacuum in the lines. How do you get the air/fuel screw back to specs; especially after adjusting the timing to the bad mixture? Had to change the plugs again after about two months because they were black and fouled worse than I have ever seen. I assume it was from the bad air/fuel.

 

I do not know the 3.0 but I am thinking what you think is the air/fuel mixture is actually your Idle screw if it is the same as a 22re. A Haynes Manual is very good at getting everything back to where it needs to be. I am guessing that the screw you think is the mixture screw is just the Idle and as far as I am aware, there really no adjusting the mixture as it is up to the computer for setting fuel and air.

Even if there was an adjustment, anything you did, in theory, the O2 sensor would get a reading and the computer should re-adjust the mixture to what it should be in my opinion. I would follow the manual and eventually it will have you to bring the screw back to its proper setting.

 

He must be talking about the idle mixture adjustment screw in the VAFM. There are lots of posts over the years about this. I have not tried to embed links but one from Jan 3 2011 was in depth. Not sure if it provides enough technical info for you. Your best bet might being buying a used one that has not been messed with.